Brake



A. Y. DODGE May 9. 1933.

BRAKE Original Filed Oct. 4, 1926 INVENTOR. AD/EL Y D0065 BY fi A TTORNE Y.

- respectively on pivots 24 and 22. The pivot means such as a double cam device 30, against Patented May 9, 1933 UNITED STATES PATENT OFFICE ADIBL Y. DODGE, OF SOUTH BEND, INDIANA, ASSIGNOR 1'0 IBE'NDIX BRAKE comm, 01 SOUTH BEND, INDIANA, A CORPORATION OF ILLINOIS BRAKE Original application fled October 4, 1928, Serial No. 139,389. Divided and this application fled 7,

1981. Serial No. 520,776.

This invention relates to brakes and is illustrated as embodied in an internal expandin automobile brake.

he present invention is a division of my pending application Serial No. 139,389, filed October 4, 1926, and is made under therequirements of the United States Patent Qfiice underrevision of Rule-42.

:AlT-Obifi'bt of the invention is to provide novel means for adjusting the brake.

An important feature of the invention relates to an automatically adjusted stop for the friction means comprising a part which is frictionally gripped to resist shifting and which is shifted from time to time as the brake lining wears. In one very desirable arrangement the automatically adjusted stop engages the pivot connectin two of the shoes and is slotted to receive a riction clamp on the backing plate of the brake.

The above and other objects and features of the invention, including various combinations of parts and desirable structure, will be apparent from the following description of the illustrative embodiment shown in the accompanying drawing, in which:

Figure 1 is a vertical section through the brake just inside the head of the brake drum illigistrating the brake shoes in side elevation; an a Figure 2 is a section substantially on the line 22 of Figure 1.

Referring to the drawing for more specific details of the invention 10 re resents a rotatable drum, at the open si e of which is arranged a suitable support or backing plate 12 arid within which are arranged three shoes 14, 16, and 18. The shoes 14 and 18 are forked at their ends to straddle opposite ends of the shoe 16, shoe 18 being connected to shoe 16.

by a pivot 20 and shoes 14 and 16 are anchored 22 passes through a relatively large opening 26 in the shoe 14, while the pivot 24' passes through a relatively large opening 28 in the shoe 16. As shown, the shoes 14 and 18 are interchangeable.

The brake is intended to be applied by the resistance of a return spring 32, the shoe 16 being applied by shoe 18 against the reslstance of an auxiliary return spring 34.

The cam device 30 includes a sleeve keyed or otherwise secured on a camshaft 36 and vided with spaced cams 38, only one of w ich is shown, engaging ooves in rollers 40 on the ends of the shoes 14 and 18 or their equivalents.

The sleeve formed with the two cams 38 is held against axial movement on the shaft 36 by a nut 42, and the rollers 40 are grooved to receive the cams 38, thus interlockin with the cams to hold the shoes against ateral movement. Preferably the grooves in the rollers are slightly wider than the cams 38, the grooves being filleted at opposite sides so that the cams will automatically cent-er themselves in the grooves. Preferably the rollers are mounted onpivots 44 and are retained by washers 46 and pins 48. The pivots 44 have eccentric portions 50 positioned in openings in the we s of the shoes 14 and 18 so that the rollers may be adjusted by turnthe pivots on these eccentric portions.

0 facilitate this adjustment the ends of the pivots may be squared to receive a socket wrench. The pivots are secured in any desired position of angular adjustment by set screws 52 threaded through the lower parts of the'webs of the shoes and which may be provided with suitable locknuts 54. p

The major feature of the resent invention relates to automatically adjusting the idle position of the shoe 16, as the limng wears during the life of a brake. In one very simple embodiment of the invention this automatically adjusted stop device includes a part 56 having an opening for one end of the pivot 20 which is slightly larger than the diameter of the pivot as indicated at'58, at least in the direction of movement of the pivot when the brake is ap lied. This clearance is equal to the desire backward movement of the shoe when the brake is released. As shown, part 56 is forked to form a slot 60 embracing a bolt 62 on the backing plate 12. A coil s ring 64, confined between the head of the bolt 62 and a friction washer 66 engaging part 56, serves to hold the stop part 56 frictionally clamped in any position to which it may be moved.

When the brake is applied, after taking up the clearance the pivot is moved until shoe 16 engages the drum, and drags the part 56 with it against the resistance of the friction washer until the brake is fully applied. Then when the brake is released, the spring 34 pulls the shoe 16 away from the drum until the pivot 20 engages the opposite side of this opening in part 56, but the spring 34 is not sufiiciently strong to shift the part 56, thus the shoe 16 is held in an idle position which is automatically determined by the amount of clearance 58.

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to that particulariembodiment or otherwise than by the terms of the appended claims.

I claim:

1. An automatic-stop for a brake comprising a plate having a slot at one end and an opening at the other end, clamping means resisting shifting of the plate including a bolt passing through the slot, and a shifting device including a part extending through the opening, which is slightly smaller than the opening.

2. An automatic stop for a brake comprising a plate having a slot and an opening, clamping means resisting shifting of the plate including a bolt passing through the slot, and a shifting device including a part extending through said opening, which part is slightly smaller than said opening.

3. A brake comprising a member moved in applying the brake, a part engaged by the member after a predetermined brake-applyin movement, and means for frictionally gripping the end of the part and imposing a drag thereon to resist shifting, the part being shifted bodily by brake-applying movement of the member after it engages the part.

4. A brake comprising a member moved in applying the brake, a part engaged by the member after a predetermined brake-applying movement having a slotted portion on the opposite side of the member, a holding device frictionally engaging the slotted portion, and gripping means carried by the holding device and resisting movement of the art. p 5. A brake comprising a member moved in applying the brake, a part engaged by the member after a predeterminedbrake-applying movement having a slotted portion n the opposite side of the member, a holdmg device passing through the slotted portion, and a friction washer carried by the holding device engaging the part.

6. A brake comprising a member moved in applying the brake, a part engaged by the member after a predetermined brake-applying movement having aslotted portion on the opposite side of the member, a holding device passing through the slotted por.tion, and a friction washer carried by the holding device engaging the part, together with a stop on the end of the device and a spring confined between the stop and the friction washer.

* 7. A brake comprising a friction member and an adjacent support, and means for determining the released position of the friction member including interengaging parts carried respectively by the friction member and the support, one of the parts having an openinoembracing the other part and larger than the other part to permit a predetermined substantially unrestricted applying movement of the friction member, the part havin the opening being shifted bodily by the other part in'case of excessive movement of the friction member.

8. A brake comprising a friction member and an adjacent support, and means for determining the released position of the friction member including interengaging parts carried respectively by the friction member and the support, one of the parts having an opening embracing the other part and larger than said other part to permit a predetermined substantially unrestricted applying movement of the friction member, the part having the opening being shifted bodily by the other part in case of excessive movement of the friction member, together with clamping means resisting shifting of the part having the opening.

9. A brake comprising a friction member and an adjacent support, and means for determining the released position of the friction member including interengaging parts carried respectively by the friction member and the support, one of the parts having an opening embracing the other part and larger than the other part to permit a predetermined substantially unrestricted applying movement of the friction member, the part havin the opening being shifted bodily by the ot er part in case of excessive movement of the friction member, together with clamping means resisting shifting of the part having the opening, the clamping means including an attaching bolt passing through a slot in the part-having the opening.

10. A brake comprising friction means having a positioning part movable therewith, a backing plate on which the friction means is mounted, and a stop having a lost-motion engagement with said part at one end and frictionally gripped to the backing plate at its other end in a manner permitting it to be brake applying movement and yieldingly gripped to the backing plate at its other end in a manner permitting it to be shifted bodily lengthwise by said part on applying 5 the brake after excessive wear.

12. A brake com rising a rotatable drum, a friction member aving a positioning part movable therewith, a backing plate on which the friction member is mounted, and a stop 10 loosely engaging said part to arrest it after a predetermined brake-applying movement, said stop being frictionally related to the backin plate in a manner permitting it to be b0 ily shifted circumferentially of the 15 drum by said part.

' 13. A brake comprising a rotatable memb r, a friction member having a positioning part movable with the friction member, a supporting member on which the friction mem- 2 her is mounted, and a stop loosely engaging said part to arrest it after a predetermined brake-applying movement, said stop being frictionally movable bodily in the direction of rotation of the rotatable member. 2 In testimony whereof, I have hereunto signed my name.

ADIEL Y. DODGE. 

